Construction of internally stacked Cu2O:CuO layers in Cu2O:CuO/Gr/ZnO heterojunctions for solar cells applications

Abstract The present work shows the construction of CuO grains on the electrodeposited Cu 2 O layer through annealing method and the photovoltaic effect of Cu 2 O:CuO/ZnO heterojunctions with graphene buffer layer is also discussed. The annealing temperature of Cu 2 O layer is varied from 100 to 300 °C. The graphene monolayer was deposited by chemical vapor deposition method. The morphology, structural and electrical properties of Cu 2 O layer were characterized by using Scanning Electron Microscopy (SEM), High Resolution Transmission Electron Microscopy (HR-TEM), X-ray Diffractometry (XRD) and I-V measurement, respectively. The Cu 2 O grains size increase as the annealing temperature increased and the CuO grains could be observed at 300°C. The graphene monolayer was successfully inserted in between Cu 2 O:CuO/ZnO heterojunction. The Cu 2 O:CuO/Gr/ZnO heterojunction shows high electrical rectification with threshold voltage of 0.5 V.